The present invention relates to the field of sheet paper feed apparatus for feeding sheets to a print mechanism, and more particularly to an apparatus which actively aligns a sheet of paper which has been fed out of a paper tray so that the skew of the sheet relative to a printer mechanism is significantly reduced.
Various active alignment systems have been employed in printer devices to align paper sheets relative to the printer mechanism. One type relies on gravity to achieve alignment. The disadvantage of such a system is that the orientation of the paper tray is necessarily constrained to particular orientations. Another system employs separate motors for the sheet pick up and paper advance mechanisms. The use of separate motors leads to additional cost and complexity.
Some sheet alignment systems use a clutch between the main paper advance mechanism and its motor, which could have a significant adverse effect on swath advance accuracy.
It is therefore an object of the present invention to provide a simple yet effective active alignment system for feeding sheets to a printer mechanism, which does not rely on gravity and does not affect the orientation of the paper tray.
A further object is to provide a sheet feed active alignment system which requires only one motor drive and yet does not require a clutch between the main paper advance mechanism and its motor.